Community Housing Cymru say that the changes to housing benefit will hit thousands of people right across Wales. The organisation that represents Housing Associations says it will lead to an increase in homelessness.
It follows claims from The Welsh Tenants Federation that 4,000 families in Wales could lose their home as a result of changes to the amount of housing benefit they receive.
The Department for Work and Pensions says that changes to Housing Benefit entitlement for working-age tenants from April 2013 'will reflect household size.'
The UK Government says that by 2013/14 an estimated 32% of working-age Housing Benefit claimants living in the social-rented sector in Great Britain will have more bedrooms than their household reasonably needs.
A body who represents people living in social housing says 4,000 families in Wales could lose their home as a result of changes to the amount of housing benefit they receive.
The Welsh Tenants Federation says that 40,000 households will be affected by the UK Government's decision to cut the amount of money paid to families under what it has called the "bedroom tax" and 10% of those would need to move home.
The changes being introduced in April mean that families who have a spare room in their home would lose 14% percent of the money they receive and those with two spare rooms would lose 25%.